Method of producing a surface sleeve for a plate cylinder for printing purposes

ABSTRACT

A surface sleeve for a rotogravure cylinder or an offset cylinder is produced by mounting a basic sleeve (20) on a supporting mandrel (10). Both the outer peripheral surface of the mandrel and the inner and outer surfaces of the basic sleeve are circularly cylindrical. On the nickel cylinder (20), a thin layer (21) of copper or nickel is deposited electrolytically, and on top of this layer an outer copper layer (22), preferably high-gloss copper, is deposited. In the case of rotogravure, this outer copper layer has a thickness which equals or slightly exceeds the desired maximum well depth of the printing pattern later to be made in the outer surface of the surface sleeve. In the case of offset printing, the outer copper layer is coated with a chrome layer in which the printing pattern is etched. After etching or engraving of a printing pattern in the outer surface of the sleeve, and after a possible chrome-plating of the etched or engraved surface, the free end parts of the surface sleeve are cut off, as the thickness of the metal layers there has become increased during the electrolytic deposits.

The present invention relates to a method of producing a surface sleevefor a plate cylinder, said method comprising arranging around asupporting mandrel a basic sleeve which is made of an electricallyconductive material such as metal, preferably nickel, and has an innersurface which is complementary to the outer surface of the mandrel,electrolytically depositing an inner metal layer on the outer surface ofthe basic sleeve, and providing on the said inner layer an outer copperlayer with a smooth circularly cylindrical surface.

The term "cyanide copper" as used in the present specification andclaims means copper which has been deposited in a cyanide-containingbath, the term "high-gloss copper" means copper which has been depositedin a bath containing gloss promoting or gloss generating additives, andthe term "chloride nickel" means nickel which has been deposited in anacidic nickel chloride bath.

Published European patent application No. 92285 describes a method ofthe above type in which a nickel layer is deposited on a mandrel havinga slightly conical outer surface. The basic sleeve thus formed isloosened and removed from the said first mandrel and slipped overanother conical mandrel which is provided with an axial bore forcompressed air with air outlets on the peripheral surface of themandrel. During the process of slipping the formed basic sleeve ofnickel over the said second mandrel, the thin-walled sleeve is exposedto a certain tangential stretching produced by means of the compressedair. While the basic sleeve is arranged on the mandrel in a stretchedcondition, its outer surface is immersed in a cyanide containing bath,and a thin layer of cyanide copper is deposited electrolytically on theouter conical surface of the basic sleeve. The mandrel with the sleevearranged thereon is then transferred to another bath in which high-glosscopper in a layer, which is substantially thicker than the cyanidecopper layer, is deposited on top of the cyanide copper layer. As theouter peripheral surface of the basic sleeve with the two coats ofcopper layers is substantially conical, and as the thickness of theelectrolytically deposited copper layers is inevitable slightly largerat the ends of the sleeve than along the intermediate part, the mandrelwith the sleeve is now arranged in a lathe, and the last depositedcopper layer is turned so that a completely circularly cylindricalsurface is achieved. Finally, yet a copper layer of so-called hardcopper is deposited electrolytically and polished, whereupon the desiredgravure pattern is produced photographically or by engraving in a mannerknown per se on the said polished outer surface of the outermost copperlayer.

In this known method the intermediate one of the deposited copper layershas to be sufficiently thick to compensate for the conical shape of thesurface at the said turning. As the thickness of the copper layer thushas to exceed the difference between the largest and the smallestdiameter of the conical shape, sleeves of a certain length may involve arelatively large thickness of the said intermediate copper layer. Theresult is that the depositing of the said intermediate metal layer,which is high-gloss copper in the known method, takes diproportionatelylong, and also the necessary turning operation contributes to increasingthe time of production and thus the cost of production for the surfacesleeve.

The present invention provides a method of the above type, in which itis possible to produce surface sleeves for plate cylinders in a mannerwhich takes substantially less time and is thus cheaper than the aboveknown method.

The method according to the invention is characterized in using amandrel and a basic sleeve having outer peripheral surfaces which have acircularly cylindrical shape, and cutting off the end parts of thesleeve after the electrolytic depositing of the outer copper layerthereon. It has been found that by starting from a basic sleeve, theperipheral outer surface of which has a circularly cylindrical shape, itis possible, without having to perform a turning operation, to obtain aperfectly circularly cylindrical surface for the outer copper layerapart from the end parts of the sleeve where the electrolytic depositingwill inevitably deposit thicker metal layers than along the intermediatepart of the sleeve. However, as these end parts are cut off in themethod according to the invention, it is merely necessary to use a basicsleeve having a length exceeding the length of the finished surfacesleeve.

As surface sleeves produced by the method according to the inventionhave a circularly cylindrical inner surface, one plate cylinder may haveseveral surface sleeves mounted on it with the same or differentorientation.

As a turning operation is avoided in the method according to theinvention, it is not necessary to deposit the relatively thickintermediate copper layer. This means that the time required fordepositing the metal layers on the basic sleeve using the methodaccording to the invention is many times shorter than the time requiredusing the known method.

The inner metal layer deposited on the basic sleeve may be of any metalwhich may adhere suitably to the basic sleeve, and on which the outercopper layer may adhere. In the method according to the invention aninner copper layer, which is then preferably cyanide copper, may bedeposited on the outer surface of the basic sleeve. Alternatively aninner nickel layer, which is then preferably chloride nickel, may bedeposited on the outer surface of the basic sleeve.

The method according to the invention may be used for producing asurface sleeve for a rotogravure cylinder. In this case the outer copperlayer is deposited in a thickness which all over exceeds the desireddepth of the wells or depressions in the printing pattern later to bemade in the surface of the outer copper layer.

However, the method according to the invention may also be used forproducing a surface sleeve for an offset printing cylinder. In this casethe outer copper layer may possibly be given a smaller thickness, but itis coated with a layer of chrome, preferably so-called matt hard-chrome,in which the printing pattern is later made in a manner known per se byetching of the chrome layer after sensitizing, copying and retouching.By replacing the normally used offset printing plates which are fixedonto an offset cylinder by a surface sleeve produced by the methodaccording to the invention, it is possible to produce endless printpatterns or print patterns in which paper waste is avoided.

The circularly cylindrical basic sleeve may be produced electrolyticallyin a conventional manner, for example by using "METTENHEIMERSchnellvernicklungsanlage", made by G.W. Mettenheimer & Co. K.G.,Kirchnerstrasse 13, 6 Frankfurt/Main, Federal Republic of Germany.Instead may be used prefabricated basic sleeves of nickel of a typewhich is generally known in connection with flexography, and which ismarketed by Stork Screens B.V., Postbus 67, 5830 AB Boxmeer, Holland.

The basic sleeve may, in principle, have any thickness, but normally awall thickness of 0.1-0.2 mm, preferably 0.125 mm is chosen, as thesleeve then obtains a suitable elasticity for being expanded and mountedon a mandrel or a plate cylinder. This elasticity further has the effectthat when the sleeve is stored without being mounted on a mandrel or acylinder, it is more difficult to impart a lasting deformation to it, ifit is exposed to incidental pressures or shocks.

In principle, the basic sleeve may be arranged on the mandrel in anysuitable manner as long as the basic sleeve is kept completely expandedand is arranged fixedly on the cylinder. In a preferred embodiment amandrel is used having an outer diameter which slightly exceeds theinner diameter of the basic sleeve, and the basic sleeve is expanded bymeans of a pressure fluid while being mounted on the mandrel. When thesupply of pressure fluid, which is preferably compressed air, ceases,the sleeve will fit tightly around the mandrel in consequence of itselasticity.

A circularly cylindrical basic sleeve as the one used in the methodaccording to the invention has the advantage compared to the conicalsleeve used in known method, that it has a uniform wall thickness whichmay be selected so as to be most suitable. When a conical basic sleeveis used having a suitable elasticity at the end where the wall thicknessis smallest, the elasticity might become inconveniently small at the endwhere the wall thickness is largest. If the elasticity is suitable atthe end where the wall thickness is largest, there is a risk of thesleeve breaking during expansion at the end where the wall thickness issmallest.

The inner metal layer which is deposited on the basic sleeveelectrolytically, is preferably a cyanide copper layer or a chloridenickel layer, and in the method according to the invention the saidinner metal layer may be deposited by removing a first deposited layerby means of reversing the current, before the final metal layer isdeposited. It has been found that this operation prepares the surface ofthe basic sleeve in such a manner that the final inner metal layeradheres better to the sleeve surface than would otherwise have been thecase. As the deposited inner metal layer only serves as a link betweenthe surface of the basic sleeve and the outer copper layer in which theprinting pattern is made, in the case of rotogravure, the inner metallayer may be made relatively thin and is normally about 2 μm. The outercopper layer deposited on the inner metal layer necessarily, in the caseof rotogravure, has to have a thickness at least equal to the largestwell depth, and the thickness of the outer copper layer may thensuitably be about 100-110 μm.

The electrolytic depositing of the metal layers on the basic sleeve maybe performed using any of the known methods. During the depositing, themandrel with the basic sleeve arranged thereon is preferably onlypartially immersed in the galvanic bath, the mandrel at the same timebeing rotated at a uniform speed. As mentioned above, the mandrel usedin the method according to the invention has to have a circularlycylindrical outer surface, and the mandrel may thus be in the form of aplate cylinder.

The cutting off of the end sleeve performed according to the method ofthe invention, is performed after the outer copper layer and any furthermetal layers have been deposited on the basic sleeve. In the case of asleeve for rotogravure, a desired printing pattern is engraved or etchedin the polished surface of the outer copper layer, and thenadvantageously, the outer surface of the surface sleeve is chrome-platedin a known manner. In the case of offset printing, the printing patternis etched into a chrome layer deposited on the outer copper layer, asmentioned above. The cutting off of the end parts of the sleeve is thenadvantageously performed only after a finished printing pattern has beenmade in the sleeve surface.

The invention will now be further described with reference to thedrawing in which

FIG. 1 is a longitudinal partially sectional side view of a platecylinder used as a mandrel,

FIG. 2 is a partially sectional side view of the mandrel or platecylinder with a basic sleeve mounted thereon and arranged in a galvanicbath for depositing of an inner metal layer,

FIG. 3 is a partially sectional side view of the same mandrel or platecylinder arranged in another galvanic bath for depositing of an outercopper layer on top of the inner metal layer, and

FIG. 4 shows the finished surface sleeve mounted on another, shortermandrel or plate cylinder fixed in a lathe for cutting off of the endparts of the surface sleeve.

FIG. 1 shows a mandrel or plate cylinder with a cylindrical casing 10which is closed at the ends by means of end walls 11 and 12. Centrallyin the end walls 11 and 12 are mounted shaft studs 13 and 14 whichproject from the end walls, and one of these shaft studs 14 has an axialair passage 15 which leads to an air chamber 16 defined inside thecylinder or mandrel. At the end of the plate cylinder or the mandrelopposite to the air passage 15, the outer surface of the cylindricalcasing 10 has a bevelled area 17, and immediately inside of this area,bores 18 which are connected to the air chamber 16 open out into thesurface of the mandrel. Further there are one or more bores 19 in thecentral area of the casing 10.

When a surface sleeve for rotogravure or offset printing is to beproduced by means of a cylinder or mandrel as shown in FIG. 1 anddescribed above, using the method according to the invention, it may bedone as described in the below examples:

EXAMPLE 1

As a basic cylinder 20 is used a nickel sleeve of the type marketed byStork Screens B.V., Boxmeer, Holland. These sleeves which are suppliedin lengths of 180 cm and have a wall thickness of 0.125 mm, have acompletely accurately circularly cylindrical surface. The casing 10 forthe mandrel or cylinder shown in FIG. 1 has a cylindrical outer surface,the diameter of which is 1/10 mm larger than the internal diameter forthe basic sleeve 20. The basic sleeve 20 is now mounted on the cylindershown in FIG. 1, one end of the sleeve being slipped over the bevelledarea 17 at the same time as compressed air is supplied to the airchamber 16 through the shaft stud 14 formed as an air supply connectingpiece. The supplied compressed air causes the nickel sleeve 20 to bestretched in a tangential direction whereby the sleeve is expanded tosuch a degree that it is easily slipped over the cylindrical casing 10.When the basic sleeve 20 is arranged on the casing 10, the supply ofcompressed air is stopped, and the nickel sleeve is now tightly fittedon the mandrel or cylinder. The basic sleeve 20 which is arranged on themandrel has to have a length which exceeds the desired length of thefinished surface sleeve. The basic sleeve 20 may suitably beapproximately 140 mm longer than the desired finished surface sleeve.

When the basic sleeve 20 has been mounted on the mandrel or thecylinder, the still uncovered parts of the cylinder surface of thecasing 10, the outer surface of the end walls 11 and 12 and the adjacentsurfaces of the shaft studs 13 and 14 are covered by means of waterprooftape 23 which is wound helically. The said tape may be of the typemarketed under the trade mark "Tesafilm 4105" by the firm "Tesa". Thecovering by means of waterproof tape 23 is made to avoid galvaniccorrosion when the mandrel or cylinder, as will be described now, isimmersed in a galvanic bath.

After the basic nickel sleeve has been mounted as described above, itsouter surface is cleaned with a mixture of 1/3 concentrationhydrochloric acid, 1/3 mineral spirits and 1/3 99% ethyl alcohol. Thisliquid mixture should not dry on the surface of the sleeve, but as soonas all impurities have been removed the sleeve surface should be rinsedwith a 99% ethyl alcohol and dried. Alternatively, the cleaning may bemade with concentrated phosphoric acid at a temperature of 85° C. Themandrel or the cylinder with the basic sleeve 20 mounted thereon is nowarranged in a container 24 containing an electrolyte 25. The shaft studs13 and 14 of the mandrel are arranged in bearings 26 so that the mandrelmay be rotated about a horizontal axis, for example by means of a motor28 via a transmission 29. The electrolyte 25 in which about 1/3 of themandrel or cylinder is immersed has the following composition: 48.2 g/lof copper cyanide, 40.0 g/l of sodium cyanide, 2.5 g/l of sodiumhydroxide and 1.5 g/l of stabilizer.

The said stabilizer is marketed under the trade name of "cupanit" by thefirm of Weiland & Cie, Bielefeld 14, Federal Republic of Germany.

The cylinder or mandrel is now rotated at a uniform speed while cyanidecopper is deposited on the exposed outer cylindrical surface of thebasic sleeve 20. By means of a sliding contact 27, such a voltage (1-2.5V) is applied to the basic sleeve, which constitutes the negativeelectrode in the galvanic bath, that a current density of 2.0-3.5 A/dm²is obtained. After about 5 minutes a thin copper layer will have beendeposited on the surface of the basic sleeve, and the current is nowreversed, a current density of 3.5-5 A/dm² being produced so that thecopper layer is again removed from the basic sleeve, and the shinynickel reappears again after about 2 minutes. After about another 2minutes the current is again reversed so that a first copper layer 21 isdeposited on the outer surface of the nickel sleeve 20. After about 1/2hour a cyanide copper layer 21 of a thickness of about 2 μm has beendeposited on the basic sleeve 20, and the cylinder is now removed fromthe cyanide copper bath, rinsed and dried.

After the outer surface of the copper layer 21 has been scoured with 5%sulphuric acid, the mandrel or cylinder with the basic cylinder mountedthereon and the first copper layer 21 is arranged partially immersed inan acidic copper bath 30 (FIG. 3) of the following composition: 200-225g/l of copper sulphate, 52-68 g/l of sulphuric acid, 30-70 ppm chlorine,0.5-0.7% by volume of Cuflex 321, and 0.5-0.7% by volume of Cuflex 320H.The mentioned additives designated Cuflex are high-gloss generatingadditives marketed by the firm of Weiland & Cie.

In this bath 30, in which the mandrel or the cylinder is rotated in amanner corresponding to that in the bath 25, a layer 22 of high-glosscopper of a thickness of 100-110 μm is deposited on top of the firstcopper layer 21. The depositing of the said outer copper layer 22 takesabout 50-80 minutes, and the current supply is governed by means of anampere-hourmeter 31 to ensure that the correct layer thickness isobtained. When the desired outer layer 22 of copper has been deposited,the outer cylindrical surface of the said copper layer may be polished,if desired, using a polishing agent such as the one marketed under thetrade mark of BRASSO®.

While the sleeve is still mounted on the mandrel or plate cylinder, asensitizing, retouching, etching and/or engraving is performed totransfer a desired printing pattern 32 in a conventional manner in therotogravure field.

To render possible an evaluation of the quality of the rotogravureprinting pattern 32 formed in the surface sleeve, the said surface may,if desired, be polished with BRASSO®, whereby the depressions or wellsof the printing pattern will appear in a transparent dark colourrendering possible an evaluation of the well depth. When the outersurface of the sleeve is then to be made ready for chrome-plating, anyremains of the polishing agent are best removed by first pouring thepolishing agent BRASSO® over the outer surface of the sleeve, thentoluene and finally the above mentioned liquid mixture. A hardchrome-plating is now made electrolytically in a conventional mannerusing a current density of 18-20 A/dm² at a voltage of 8-12 volt and atemperature of 50° C.±2° C. After the hard chrome-plating in which achrome layer 33 (FIG. 4) is formed, the waterproof tape 23 is removed.The mandrel or cylinder is then placed in a holder, and the air passage15 is again connected to a compressed air source whereby the finishedsurface sleeve is stretched tangentially so that it can easily beremoved from the mandrel. The now almost finished surface sleeve isarranged on another and shorter mandrel or cylinder 34 using compressedair. Then the mandrel or cylinder 34 is arranged in a chuck 36 of alathe in which the surface sleeve end parts 35, which are not completelycylindrical, as explained above, are cut off by means of a cutting-offtool 37 so that the surface sleeve obtains the desired length. Inconnection with the cutting, the end edges of the surface sleeve mayalso, if desired, be rounded by means of tools 38 to reduce the wear,partly on the doctor blade used in connection with the rotogravurecylinder, and partly on the edges of the sleeve.

If the surface sleeve is to be used for offset printing, no etching orengraving of a printing pattern is made in the outer surface of theouter copper layer 22, but the said layer 22 is provided with a layer ofhard-chrome of about 6 μm. After the chrome-plating, sensitizing,copying and retouching is carried out as is well-known in the offsetprinting field, and then the chrome layer is etched so that it it etchedaway in the places which are to receive colour. The end parts 35 of thethus produced surface sleeve are cut off in the same manner as describedabove.

EXAMPLE 2

A surface sleeve for rotogravure or offset printing is produced in thesame manner as described in Example 1, an inner layer of chloride nickelbeing deposited on the outer surface of the basic sleeve 20 instead ofan inner cyanide copper layer. The mandrel or the cylinder with thebasic sleeve 20 mounted thereon is arranged as described in Example 1 inthe container 24 in which the electrolyte 25 is a generally known acidicnickel chloride bath, for example produced as follows: 60 kg of nickelchloride is added to 60 liter of lukewarm corporation water, stirred andcooled. Then 60 liter of concentrated hydrochloric acid is addedtogether with a suitable amount of surfactant which may be for examplesulphonic detergent of the type used as dishwashing liquid.

The cylinder is rotated as previously described, and such a voltage (4-5volt) is applied that the current density becomes 2.0-3.5 A/dm². Afterabout 5 minutes a layer of chloride nickel has been deposited, and it isremoved again by means of reversing the current - maintaining the samevoltage and current density. Thus, advantageously, also a small part ofthe material of the basic sleeve 20 is removed from its outer surface.The current is again reversed, and in about 5 minutes a layer ofchloride nickel of a thickness of about 1 μm has been deposited. Thecylinder is now rinsed over the nickel bath with clean cold water andtransferred into the acidic copper bath 30 before the outer surface ofthe cylinder dries, and then the outer copper layer 22 and a chromelayer 33 are deposited, printing patterns 32 are transferred, and theend parts 35 of the formed surface sleeve are cut off as described inExample 1.

The completely finished surface sleeve which is produced by one of themethods described in the above examples is now mounted on a rotogravureplate cylinder or an offset printing plate cylinder of the type shown inFIG. 1. This cylinder may have such a length that two or more surfacesleeves may be mounted on the same cylinder, and as both the outersurface of the plate cylinder and the inner surfaces of the surfacesleeves are circularly cylindrical, these surface sleeves may beoriented as desired.

We claim:
 1. A method of producing a surface sleeve for a platecylinder, said method comprising, arranging a basic sleeve made from anelectrically conductive material and having inner and outer circularlycylindrical peripheral surfaces, tightly around an outer circularlycylindrical peripheral surface of a supporting mandrel, electrolyticallydepositing an inner metal layer on the outer peripheral surface of thebasic sleeve, electrolytically depositing an outer copper layer with asmooth substantially circularly cylindrical outer surface, on said innermetal layer, and cutting off opposite outer end portions of the sleeveafter depositing the outer copper layer thereon.
 2. A method accordingto claim 1, wherein the basic sleeve is made from metal.
 3. A methodaccording to claim 2, wherein said metal is nickel.
 4. A methodaccording to claim 3,wherein the inner metal layer is a layer of copper.5. A method according to claim 4, wherein said copper is cyanide copper.6. A method according to claim 3, wherein the inner metal layer is alayer of chloride nickel.
 7. A method according to claim 5 or 6, whereinthe thickness of said inner metal layer is about 2 μm.
 8. A methodaccording to claim 3, wherein the inner metal layer is formed bydepositing nickel on the outer surface of the basic sleeve.
 9. A methodaccording to claim 8, wherein said nickel is chloride nickel.
 10. Amethod according to claim 3 wherein the outer copper layer is depositedin a thickness which all over exceeds the desired well depth in aprinting pattern so as to produce a surface sleeve for a rotogravurecylinder.
 11. A method according to claim 3, further comprising coatingthe outer copper layer with a layer of chrome in which a printingpattern is later to be made, so as to produce a surface sleeve for anoffset printing cylinder.
 12. A method according to claim 11, whereinsaid chrome is matt hard chrome.
 13. A method according to claim 3,wherein the basic sleeve arranged on the mandrel is a prefabricatedsleeve.
 14. A method according to claim 6, wherein the basic sleeve hasa wall thickness of 0.1-0.2 mm.
 15. A method according to claim 3,wherein the mandrel has an outer diameter slightly exceeding the innerdiameter of the basic sleeve, the basic sleeve being expanded by meansof a pressure fluid while it is being arranged on the mandrel.
 16. Amethod according to claim 3, wherein depositing of the inner metal layerincludes electrolytically depositing an initial metal layer on the outersurface of the basic sleeve in an electrolytic bath by providing acertain polarity, removing said initial layer by reversing saidpolarity, and finally depositing said inner metal layer.
 17. A methodaccording to claim 3, wherein the outer copper layer is deposited in athickness of about 100-110 μm.
 18. A method according to claim 3,wherein said inner and outer layers are electrolytically deposited byonly partially immersing the mandrel with the basic sleeve arrangedthereon into an electrolytic bath and rotating the mandrel at asubstantially uniform speed while immersed in said bath.
 19. A methodaccording to claim 3, wherein the mandrel is a plate cylinder.
 20. Amethod according to claim 3, wherein a printing pattern is provided inthe outer peripheral surface of the surface sleeve produced prior tocutting off said opposite outer end portions.
 21. A method of producinga surface sleeve for a plate cylinder, said method comprising, arrangingthe basic nickel sleeve having inner and outer circularly cylindricalperipheral surfaces tightly around an outer circularly cylindricalperipheral surface of a supporting mandrel, electrolytically depositingan inner metal layer on the outer surface of the basic sleeve,electrolytically depositing an outer copper layer with a smoothsubstantially circularly cylindrical outer surface on said inner metallayer, providing in said outer cyanide copper layer a rotogravureprinting pattern comprising wells having a depth not exceeding thethickness of said outer layer, and cutting off opposite outer endportions of the surface sleeve so produced.
 22. A method according toclaim 21, wherein said inner metal layer is a layer of cyanide copper.23. A method according to claim 21, wherein said inner metal layer is alayer of chloride nickel.
 24. A method of producing a surface sleeve foran offset printing cylinder, said method comprising arranging a basicnickel sleeve having inner and outer circularly cylindrical peripheralsurfaces tightly around an outer circularly cylindrical peripheralsurface of a supporting mandrel, electrolytically depositing an innermetal layer on the outer peripheral surface of the basic sleeve,electrolytically depositing an outer copper layer with a smooth,substantially circularly cylindrical outer surface on said inner metallayer, coating said outer copper layer with a layer of matt hard chrome,providing an offset printing pattern in the outer peripheral surface ofsaid chrome layer, and cutting off opposite outer end portions of thesurface sleeve so produced.
 25. A method according to claim 24, whereinsaid inner metal layer is a layer of cyanide copper.
 26. A methodaccording to claim 24, wherein said inner metal layer is a layer ofchloride nickel.
 27. A surface sleeve for a plate cylinder andcomprising a basic nickel sleeve having inner and outer circularlycylindrical peripheral surfaces, an inner metal layer electrolyticallydeposited on the outer peripheral surface of the basic sleeve, and anouter copper layer with a smooth, substantially circularly cylindricalouter peripheral surface electrolytically deposited on said inner metallayer and having a rotogravure printing pattern provided therein,opposite outer end portions of the surface sleeve having been cut offafter deposition of said outer copper layer thereon.
 28. A surfacesleeve for an offset printing cylinder and comprising a basic nickelsleeve having inner and outer circularly cylindrical peripheralsurfaces, an inner metal layer electrolytically deposited on the outerperipheral surface of the basic sleeve, an outer copper layer with asmooth, substantially circularly cylindrical outer peripheral surfaceelectrolytically deposited on said inner metal layer, and a coating of amatt hard chrome layer arranged on the peripheral surface of the outercopper layer and having an offset printing pattern provided thereon,opposite outer end portions of the surface sleeve having been cut offafter deposition of said outer copper layer thereon.